Reserves for Insurance Losses and Loss Adjustment Expenses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Gross reserves for insurance losses and loss adjustment expenses, beginning balance	$ 119	$ 122
Less: Reinsurance recoverable	72	81
Net reserves for insurance losses and loss adjustment expenses	58	43	$ 47	$ 41
Current year	87	61
Prior years	1	(3)
Total net insurance losses and loss adjustment expenses incurred	88	58
Current year	(49)	(36)
Prior years	(28)	(20)
Total net insurance losses and loss adjustment expenses paid or payable	(77)	(56)
Plus: Reinsurance recoverable	75	80
Gross reserves for insurance losses and loss adjustment expenses, ending balance	$ 133	$ 123